Not 100% sure, but I believe heating SS anneals it.
The Official 1HD-T/FT Fuel Pump Mod Tuning Thread
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Not 100% sure, but I believe heating SS anneals it.
Hey guys, my 1hdt died and I got a 1hz for next to nothing. I've bolted my intake + exhaust manifold gturbo ect onto it.
Its got the standard 10mm pump on it which is tired. I've been doing some research on putting my 1hdt pump on it.
Few things Ive found from the fsm, the upper 1hz timing advance spec is close to the lower 1hdt spec. The crack pressure on the 1hdt injectors are around 20% higher than the 1hz. Static timing also is set around 20% more advanced than the 1hz which would allow it to build pressure longer before opening the nozzle.
Talking to a few people they think if I play around with the timing I should be able to get it to run reasonably well.
Anyone else done it or want to share their thoughts?
Its got the standard 10mm pump on it which is tired. I've been doing some research on putting my 1hdt pump on it.
Few things Ive found from the fsm, the upper 1hz timing advance spec is close to the lower 1hdt spec. The crack pressure on the 1hdt injectors are around 20% higher than the 1hz. Static timing also is set around 20% more advanced than the 1hz which would allow it to build pressure longer before opening the nozzle.
Talking to a few people they think if I play around with the timing I should be able to get it to run reasonably well.
Anyone else done it or want to share their thoughts?
Do some searching, it's been talked about here before, pretty sure it's been done.
I tried the opposite without success (1HZ IP onto 1HD-T). As you note, fuel pressures and timing are quite different.
what 6mm pin? the fuel pin in my FT is 10.9mm diameter
You can surface harden the pin by heating it cherry red and quenching in light oil.
I notice those aftermarket covers are like mine.... I just weld the stock one and use a different spring.
I notice those aftermarket covers are like mine.... I just weld the stock one and use a different spring.
Is that true for stainless steel? Will gladly give it a go, but don't want to anneal it.
Sorry, misread that your pin WAS stainless.
Most pump internal parts are very hard. not drillable, even if you grind the surface off.
I believe the pins are the same way . I had 25 year old original pins that only have a slight wear line, which is easily polished out.
Grinding custom ones is probably cheaper and easier on tooling, using stainless.
Most pump internal parts are very hard. not drillable, even if you grind the surface off.
I believe the pins are the same way . I had 25 year old original pins that only have a slight wear line, which is easily polished out.
Grinding custom ones is probably cheaper and easier on tooling, using stainless.
Cheers yotahead. Yeah the OEM pins are hardened, and I think chrome plated and polished. I found my OEM one hard to grind
Alright got the 1hdt pump on the 1hz. Started timing off very conservatively at .80 and it was a total smoke show wouldn't idle ect. I cant get my dial gauge back into the pump with the lines fitted so I just knocked it somewhere into the middle of the range. The thing actually starts and runs half decently. Still
Tommorrow I'll try again with the gauge. Although I dont know how well its going to help me as there isnt exactly a spec for this pump on this motor. Any tips on what to look for when timing? Knocking smoke pyros ect.
Tommorrow I'll try again with the gauge. Although I dont know how well its going to help me as there isnt exactly a spec for this pump on this motor. Any tips on what to look for when timing? Knocking smoke pyros ect.
Finally found a lever mechanism with different ratios that fit into the pump housing without too much modifications. When the AFC is maxed out there is plenty CC's left in the rest of the pump. IMO the only way to get these out is increase the main fuel screw, but this will add smoke on low RPM as well. To prevent this, you have to alter the mechanism i guess. I can measure a few more micrometer on the collar now by moving the AFC so that's a good thing. I can get AFR's now of 22 on 3000 rpm where I couldnt get it lower than 30 before on 28psi. Still have to do some tuning, could be another day of work as always..
Finally found a lever mechanism with different ratios that fit into the pump housing without too much modifications. When the AFC is maxed out there is plenty CC's left in the rest of the pump. IMO the only way to get these out is increase the main fuel screw, but this will add smoke on low RPM as well. To prevent this, you have to alter the mechanism i guess. I can measure a few more micrometer on the collar now by moving the AFC so that's a good thing. I can get AFR's now of 22 on 3000 rpm where I couldnt get it lower than 30 before on 28psi. Still have to do some tuning, could be another day of work as always..
Nice work. If you can wrap your head around all those moving parts, you've done well
Do you have any way to confirm this?
My understanding was that the cam plates are different, but that's unverified. Just curious.
Yes just a caliper. You can reach it by the ascd hole. Only 1hdft is higher but doubt it will make much difference. Tried swapping plates before and still doesn't make much more (drivable) power so i think part the culprit is in the control mechanism to get both proper low end and high end fuel.
Measured 1 time a 1hz pump so maybe coincidence.
Still have headaches of that mechanism.
Measured 1 time a 1hz pump so maybe coincidence.
Still have headaches of that mechanism.
Cool. Let us know how you go after changing the governor lever mechanism.
Alright, got the gauge back on it and it’s actually at .75.
I think I must of stuffed up last time.
I’ve set it to a conservative 1.00 now and will see how it goes.
Also I’ll be getting the injectors checked now that I’m putting 200hp ~ worth of fuel in the thing
I think I must of stuffed up last time.
I’ve set it to a conservative 1.00 now and will see how it goes.
Also I’ll be getting the injectors checked now that I’m putting 200hp ~ worth of fuel in the thing
Is already in but now still cant get it lower than 22:1afr. Still cant tune for more fuel on high rpm while maintaining low rpm off boost fuel. Ive wrapped my head around the afc lever today and it just hasnt enough travel and found a few ways to get it sorted. Should have to do that first before swapping the fulcrum lever. At least i can leave the pump on the car now so maybe tomorrow. Looks like all the ve pump information on the web is slightly different from how it works in the 1hdt pump. So not all the tricks the for example cummins guys do works as good on our pumps.
I was looking at this last year. Two things limit AFC lever travel.
1, how deep a useful grind you can putdo on the aneroid pin,
2, clearance for the AFC/governor stop lever in the underside of the housing.
In theory, you should be able to retro fit the threaded sleeve for the AFC/aneroid pin from a Bosch VE pump so you can run a 12 mm aneroid pin from a Bosch (Cummins) IP. (vs 11mm pin in Denso IP)
A larger diameter aneroid pin would give slightly more scope when grinding a pin to give a greater range of travel from min to max travel for the follower pin.
Some clearancing under the AFC housing could also free up some travel.
My experience is that you already can grind the pin more than the guide pin will travel. So i was thinking for a longer guide pin and grind the nut with the spring that's behind the guide pin. That will give almost millimeters of extra travel of the afc lever and that's a lot in pump world. An 12mm aneroid pin might be limit travel of the afc lever even more as there isnt much room in the housing to move.
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Correct.
Starting with a larger diameter pin means your minimum fuel position is less than zero in comparison to the std diameter pin (hope that makes sense).
By starting with a lower base, you gain a little more overall travel. If everything else is the same, a 12mm pin gives you .5mm extra travel from zero, to max. As you said, 1mm here is a lot. Even .5mm is significant.
a combination of 12mm aneroid pin, and grinding could make a big difference.